build(deps): bump Externals/zlib from 0f51fb4 to 534864b

Bumps [Externals/zlib](https://github.com/madler/zlib) from `0f51fb4` to `534864b`.
- [Release notes](https://github.com/madler/zlib/releases)
- [Commits](madler/zlib@0f51fb4...534864b)

---
updated-dependencies:
- dependency-name: Externals/zlib
  dependency-type: direct:production
...

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